The overall objective of the research in this laboratory has been to attempt to identify antigens in intercellular tissues and pericellular substances which play a role in immunological reaction in vivo. More recently, we have been trying to determine to what extent such antigens, aside from cell related histocompatible ones, contribute towards the rejection of a graft. This includes our interest in an understanding of the immune mechanisms responsible for the complex vascular changes which accompany such rejection.